1. Field of the Invention
The present invention relates to a novel plant species ssamchoo and to the breeding method thereof. More particularly, the present invention relates to a novel plant species ssamchoo which was developed by aneuploid breeding method between Chinese cabbage and cabbage and to the breeding method of ssamchoo. 
2. Description of Prior Art
In some cases, in Korea, Chinese cabbage is eaten uncooked, but in usual cases, eaten as kimchi. When eating cabbage as leaf-wrapped rice or fresh salad, the elliptical shape, rigid stalks and oval shapes of cabbage leaves are problems and not so convenient for eating. Though the above problem is not apparent in lettuces particularly in the case of lettuce-wrapped rice, it is not so suitable for salad, either.
Upon consideration of the above points, in order to obtain a novel plant species that can be used as a substitute for lettuce and as the material for salad, the inventors achieved the present invention ssamchoo in the way by crossing as seed parent the plant selected through 5th generation of aneuploid (2n=25) obtained by repeatedly crossing the sesquidiploid with Chinese cabbage, which was obtained by crossbreeding a hybrid between Chinese cabbage and cabbage with Chinese cabbage with as pollen parent the plant selected through 5th generation of aneuploid (2n=26) obtained by repeatedly crossing the sesquidiploid generation with Chinese cabbage, which was obtained by crossbreeding a hybrid between Chinese cabbage and cabbage with Chinese cabbage, and investigated the chromosome number of it to be 2n=40.
That is, the chromosome number of ordinary Chinese cabbage is 2n=20, the chromosome number of cabbage is 2n=18, the chromosome number of leaf mustard is 2n=36 and the chromosome number of rape is 2n=38, but that of novel plant species invented by the present inventor is 2n=40 and it is a nonexistent plant even now.
Consequently, the purpose of the present invention is to provide novel plant species developed from a hybrid between Chinese cabbage and cabbage with Chinese cabbage by a aneuploid breeding method.
Another purpose of the present invention is to provide the breeding method of the above novel plant species ssamchoo. 
With the background in mind, the present invention is aimed to provide a novel plant species, ssamchoo. 
Another object of the present invention is to provide the breeding method of a novel plant species, ssamchoo. 
The purpose of the present invention was accomplished by developing the novel plant in the way of crossing B2F5 as seed parent selected through 5th generation of aneuploid (2n=25) obtained by repeatedly crossing the sesquidiploid with Chinese cabbage, which was obtained by crossbreeding a hybrid between Chinese cabbage and cabbage with Chinese cabbage with the plant as pollen parent selected through 5th generation of aneuploid (2n=26) obtained by repeatedly crossing the sesquidiploid with Chinese cabbage, which was obtained by crossbreeding a hybrid between Chinese cabbage and cabbage with Chinese cabbage, and accomplished by investigating the feature of novel plant species and then by growing plant having the genetically equal chromosome number of 2n=40 from tissue culture in part.